Add VDSO global setting and mapping to sys property.

This will help us run P/H experiments by controlling the VDSO
system property through P/H.

Bug: 70518189
Test: Will manually test it later through opt-in P/H experiment.
Change-Id: I95fd51085aed229358e2cefd472da1116c6073b3
diff --git a/core/tests/coretests/src/android/provider/SettingsBackupTest.java b/core/tests/coretests/src/android/provider/SettingsBackupTest.java
index 7cfedc8..ce29c70 100644
--- a/core/tests/coretests/src/android/provider/SettingsBackupTest.java
+++ b/core/tests/coretests/src/android/provider/SettingsBackupTest.java
@@ -349,6 +349,7 @@
                     Settings.Global.SYS_STORAGE_FULL_THRESHOLD_BYTES,
                     Settings.Global.SYS_STORAGE_THRESHOLD_MAX_BYTES,
                     Settings.Global.SYS_STORAGE_THRESHOLD_PERCENTAGE,
+                    Settings.Global.SYS_VDSO,
                     Settings.Global.TCP_DEFAULT_INIT_RWND,
                     Settings.Global.TETHER_DUN_APN,
                     Settings.Global.TETHER_DUN_REQUIRED,